1. Field of the Invention
The present invention relates in general to the field of information handling systems, and more particularly to a method and system for information handling system bus data transfers with multiple protocols on a set of wirelines.
2. Description of the Related Art
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
In order to improve the interoperability of information handling systems with each other and with other devices, manufacturers have collaborated to develop standards for transferring information over busses. For instance, bus protocol standards define how signals are sent across wire line traces so that devices made by different manufactures may communicate with each other and with information handling systems made by different manufacturers. The bus protocol standards ensure the interoperability of external devices that connect with sockets typically located at the back of an information handling system and the interoperability of internal devices that connect with sockets typically configured as card slots. For example, common external devices include monitors, printers, scanners and audio systems which connect to sockets for common use, such as Universal Serial Bus (USB) sockets, or which connect to sockets for specialized use, such as graphics card socket connectors that extend from a graphics card inserted into a slot. Common internal devices include storage devices such as hard drives, floppy drives, CDROM drives, random access memory (RAM), and host adapters for connecting bus to bus, e.g. a PCI to 1394 host adapter. Common bus protocols include USB, Infiniband, 1394, 3GIO (PCI Express), Serial Advanced Technology Attachment (SATA) and Serial Attached SCSI.
One difficulty with communicating information through busses is that information handling system motherboards generally are designed to include separate wire line traces and connectors for each supported bus protocol. Thus, the greater number of supported protocols, the more complex the motherboard design. One simplification for motherboard design is reliance on serial busses, which use an embedded clock to send bits of information sequentially across a line, instead of parallel busses which use a separate strobe line to send bits simultaneously across separate lines. Reliance on serial busses has increased with the increased data transfer rates available with differential busses that use separate lines to send positive and negative signals. A differential serial bus transfers data at rates comparable to or better than a parallel bus while using less traces, thus improving information handling system performance with reduced motherboard complexity.
Although high speed differential serial busses generally use the same design layout rules, separate line traces are typically required for each bus protocol since each protocol sends unique signals. Further, each bus protocol typically has a unique form factor so that incompatible devices cannot connect with a given bus protocol socket. Thus, for each bus protocol supported by an information handling system, the motherboard design typically includes separate sets of routed wire lines and separate connectors. Manufacturers generally include a number of different bus protocols in an information handling system to increase compatibility with devices. However, the greater the number of supported protocols, the greater the number of wire lines and connectors needed to support the protocols resulting in greater expense and complexity.